Yamaha cd player spindle problem??
TJB
Just replaced the laser unit and it detects the CD and the spindle motor
starts up ok. Hit the play button and the unit plays okay for about 15
minutes then starts to slow down, speed generally wanders around and
eventually stops and indicates there is no CD present.
Is this likely to be a motor problem? If not any hints? This unit is not
the best to try and work on as you can't get to anything while the it is
playing
Thanks for any help
TJB
N Cook
news:Xns98EBC7D89...@203.16.214.243...
Try electrically disconnecting the motor (cut trace maybe) and running it,
the motor in isolation, from a bench power supply to see if its a bearing
problem.
Only low voltage, 1 to 2volts at most usually
--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
TJB
news:esjet1$dgr$1...@inews.gazeta.pl:
I did try running the motor from a low voltage and it ran okay but maybe
I should let it run for 30min or so and see what happens???
TJB
Mark D. Zacharias
They had problems with shorted brushes on those motors...
Mark Z.
TJB
news:IQcHh.5628$P47....@newssvr22.news.prodigy.net:
Is the problem I described above a symptom of shorted brushes. I
originally though it may be an overheating problem. Are there any other
faults which could manifest themselves as described?
Is it possible to clean/repair these motors or do you simply just go and
buy another one?
Thanks for the help so far
TJB
N Cook
The problem is removing the interference fit platter from the spindle
without deforming the platter or if replacing the motor messing up the
internal contact fingers by indirectly pulling at the spindle as well as
original problem.
Mark D. Zacharias
The motor can be checked with an ohmmeter at a low ohms range setting, while
SLOWLY rotating the motor. It should normally read 10 to 12 ohms or so. The
reading will vary while turning, but should not be short-circuit or open at
any one spot in it's rotation.
It is often possible to clear the short using an aerosol cleaner / lubricant
with a pinpoint applicator, sprayed through the slits at the bottom, aimed
at the brushes, while rotating manually, alternating with blowing it out
with a compressor. It's usually necessary to repeat several times before the
short clears. Blow out the excess cleaner with the compressor. You really
need to understand the construction of small motors so you can "aim" the
cleaner at the brushes.
Mark Z.
Sam Goldwasser
See: http://www.repairfaq.org/sam/cdfaq.htm#cdmot
--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html
Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
TJB
Thanks, I will try the motor rotation test and see what happens.
Any thing else worth checking??
Thanks
TJB
TJB
news:6wvehd5...@blue.seas.upenn.edu:
Great repair faq!
Thanks
TJB
TJB
news:Xns98EDC44D7...@203.16.214.243:
I measured the spindle motor resistance, it varied between 3 and 5 ohms.
Normal??? Doesn't seem to have any slop in the bearing, but I put a
very small drop of machine oil on it anyway.
I also noticed another possible problem with this deck: the clearance
from the bottom of a cd in the holder to a plastic locating pin which
pushes through a slot in the turntable is very very small. Possibly the
spindle platter height is to low? There is a remote chance of a cd
rubbing on this pin as it is playing.
Anyone have a value from the correct platter height? I measured from the
chassis to the very start of the black plastic platter at 8.3mm, oops I
probably should have measured to the flange where a cd would sit.
Anyway can anyone let me know what the platter height measurement should
be : I guess that would be from where a cd sits to the chassis??
Thanks
TJB
Mark D. Zacharias
I'm almost certain the 3 to 5 ohms is too low. Spindle height is not
standarized from model to model, but I believe it needs to be about 2 to 3
mm clearance from the pickup lens to the underside of the disc.
Mark Z.
Ken G.
cd players do that .
It takes a pretty free spining motor to run right at such low speeds .
Put a drop of oil at the top bushing .
I have had some luck running the motor isolated like already mentioned
but using 6 or 9 volts to blow the carbon out of it so to speak ... that
may or may not last . New motors are cheap
Sam Goldwasser
> >> Great repair faq!
> >>
> >> Thanks
> >> TJB
> >>
> >
> > I measured the spindle motor resistance, it varied between 3 and 5
> > ohms. Normal??? Doesn't seem to have any slop in the bearing, but I
> > put a very small drop of machine oil on it anyway.
> >
> > I also noticed another possible problem with this deck: the clearance
> > from the bottom of a cd in the holder to a plastic locating pin which
> > pushes through a slot in the turntable is very very small. Possibly
> > the spindle platter height is to low? There is a remote chance of a cd
> > rubbing on this pin as it is playing.
> >
> > Anyone have a value from the correct platter height? I measured from
> > the chassis to the very start of the black plastic platter at 8.3mm,
> > oops I probably should have measured to the flange where a cd would
> > sit.
> >
> > Anyway can anyone let me know what the platter height measurement
> > should be : I guess that would be from where a cd sits to the
> > chassis??
> >
> > Thanks
> > TJB
>
> I'm almost certain the 3 to 5 ohms is too low. Spindle height is not
> standarized from model to model, but I believe it needs to be about 2 to 3
> mm clearance from the pickup lens to the underside of the disc.
>
> Mark Z.
I agree that 3 to 5 ohms sounds low. Try this quick test: Disconnect
the motor from the CD player and run it for a few seconds *only* at
8 or 10 V. This may blow out some of the crud but shouldn't damage
an otherwise healthy motor. Then retest and report back. :)
TJB
3237.bay.webtv.net:
Unfortunately the motor was slowing down too much and the audio was
breaking up horribly and then the motor would eventually stop.
I will probably replace the motor
Thanks
TJB
TJB
Pickup lense seems to be around 2mm, its that damn turntable locating
pin (don't know why is has to be sooo big) that seems to close for
comfort.
Tried it for a few secs at a higher voltage; the motor still measures
around 3-5 ohms turning it slowly by hand. maybe I should just change
it. Seems simple enough the platter is just a tight fit and should just
pull straight off.
Thanks
TJB
TJB
news:Xns98F19793...@203.16.214.243:
Looking at a replacement motor. The original is RF-310T-11400. The only
motor I have found readily available is an RF-310. Is there any
difference between the RF310 and the RF310T ??
Also avalable is a MDN4RA, looks like that is also the same physical
size. Not sure if its suitable as there doesn't seem to be much info on
any of these motors.
Thanks
TJB
Mark D. Zacharias
Try to get the exact same motor number. The different model suffixes often
relate to the length of the motor spindle (shaft).
Carefully measure the spindle platter height before you remove it. Also, be
aware that you won't likely be able to get it installed on the new motor
"quite" true, meaning that you will probably have some spindle motor wobble
after the new motor is installed. Shouldn't really be a problem, but I
thought it should be mentioned...
Mark Z.
Ron(UK)
height gauge moulded onto the plastic frame, maybe yours has something
similar
Ron(UK)
--
Lune Valley Audio
Public Address Systems
Hire Sales Maintenance
www.lunevalleyaudio.com
TJB
>
> Try to get the exact same motor number. The different model suffixes
> often relate to the length of the motor spindle (shaft).
>
> Carefully measure the spindle platter height before you remove it.
> Also, be aware that you won't likely be able to get it installed on
> the new motor "quite" true, meaning that you will probably have some
> spindle motor wobble after the new motor is installed. Shouldn't
> really be a problem, but I thought it should be mentioned...
>
>
> Mark Z.
>
>
>
Mark, this may be a dumb question but I am going to ask anyway. Why
would putting the platter onto a new motor cause any more wobble than
with the current motor??? It has one of those pressed on plastic
platters and assuming I don't bend the spindle.
TJB
TJB
news:BYudnV8NQd2...@bt.com:
> Pioneer cd assemblies have a little 'break off' U shaped turntable
> height gauge moulded onto the plastic frame, maybe yours has something
> similar
>
> Ron(UK)
>
I'll just measure it with calipers. I was hoping someone would have the
correct measurement from a manual, as I am concerned about the plastic
locating lug height being a problem.
Thanks
TJB
Mark D. Zacharias
It's just been my experience. The original was pressed on with a machine.
You and I press it on by hand and it doesn't wind up that the disc will
rotate quite as flat as the original once the job is done. Like I said, it;s
not really a big deal. The focus servo will just have to work a little
harder.
Mark Z.
TJB
Thanks Mark. I will order a motor and see what happens
TJB
TJB
news:Xns98F3D1585...@203.16.214.243:
Just fitted a new motor. Can't tell if it has more wobble or not. I
don't have any way to measure the wobble but from an 'eye ball' point of
view, it doesn't seem to spin all that flat, (orig may have been the
same). but the focus tracks the cd and the unit plays just fine.
Thanks everyone for your help
TJB
Mark D. Zacharias
Woo-Hoo!
Glad that worked out for you.
Mark Z.
TJB
Thanks Mark, I still have this uncomfortable feeling about that
turntable locating pin. If the laser assembly springs start to sag any
cd you play will start to rub on this pin; there seems to be just over
1mm clearance. Oh well I will just have to see what eventuates.
Cheers
TJB